let str = 'hello'
let num = 123
let flag = false
let un = undefined
let nu = null

let obj = {}
let arr = []
let fn = function () {}
let date = new Date()

// console.log(str instanceof String);  // false
// console.log(num instanceof Number);  // false
// console.log(flag instanceof Boolean);  // false
// console.log(un instanceof undefined);
// console.log(nu instanceof null);


// console.log(obj instanceof Object);  // 
// console.log(arr instanceof Array);  // 
// console.log(fn instanceof Function);  // 
// console.log(date instanceof Date);  // 

console.log(arr instanceof Array);  // true
console.log(arr instanceof Object);  // true


var array = []  // new Array()

// array.__proto__ = Array.prototype

// Array.prototype.__proto__ = Object.prototype